Soil compacting apparatus adapted to operate with rotating unbalances

ABSTRACT

The invention concerns soil compacting apparatus which is adapted to operate with rotatable unbalance and which will be positively driven along a chain by means of a driven sprocket wheel, such chain spanning the soil surface to be compacted. The apparatus of the invention is characterized in that it comprises soil compacting apparatus which is adapted to operate with rotatable unbalance and which will be positively driven along a chain by means of a driven sprocket wheel, characterized in that said apparatus comprises a chain guiding system which is settable in a first position in which the chain will be maintained in engagement with the sprocket wheel in the zone of a circumferential sector, and which is movable from said first position towards a second position in which the chain can be detached from engagement with the sprocket wheel.

United States Patent Borsutzki et al.

[ 51 Sept. 26, 1972 [54] SOIL COMPACTING APPARATUS ADAPTED TO OPERATE WITH ROTATING UNBALANCES [72] Inventors: Eberhard Borsutzki, Rotenburg; Gerhard Liehmann, Lingen/Ems, both of Germany [73] Assignee: Deutsche Schachtbauund' Tiefbohrgesellschaft mbH, Lingen, Germany; by said Liehmann [22] Filed: May 6, 1970 [21] Appl. No.: 35,118

[30] I Foreign Application Priority Data June 27, 1969 Germany ..P 19 32 635.3

[52] US. Cl. ..94/50 V, 74/226 [51] Int. Cl ..E0lc 19/28 [58] Field of Search ..94/48, 50; 74/89.2, 89.21, 74/89.22, 226, 242.11 S

3,403,474 10/ 1 968 Spasoff ..74/89.22 X 3,589,203 6/1971 Hines ..74/226 1,874,957 8/1932 Gardiner ..94/45 2,084,068 6/1937 Vinton ..94/45 2,334,717 11/1943 Long ..94/45 2,449,710 9/1948 Miller ..94/44 2,603,132 7/1952 Miller ..94/45 3,292,512 12/ 1 966 Schaperclaus ..94/48 Primary Examiner-Jacob L. Nackenoff Attorney-Olson, Trexler, Wolters & Bushnell 5 7] ABSTRACT The invention concerns soil compacting apparatus which is adapted to operate with rotatable unbalance and which will be positively driven along a chain by means of a driven sprocket wheel, such chain spanning the soil surface to be compacted. The apparatus of the invention is characterized in that it comprises soil compacting apparatus which is adapted to operate with rotatable unbalance and which will be positively driven along a chain by means of a driven sprocket wheel, characterized in that said apparatus comprises a chain guiding system which is settable in a first position in which the chain will be maintained in engagement with the sprocket wheel in the zone of a circumferential sector, and which is movable from said first position towards a second position in which the chain can be detached from engagement with the sprocket wheel.

8 Claims, 4 Drawing Figures PATENTEDSEP26 I972 sum 1 nr 3 QN a N WZW m Z PATENTEH SEP 2 6 I972 SHEET 2 [1F 3 SOIL COMPACTING APPARATUS ADAPTED TO OPERATE WITH ROTATING UNBALANCES The invention relates to soil compacting apparatus which is adapted to operate with rotatable unbalance, or with rotatable unbalances, and which will be positively driven along a chain by means of a driven chain sprocket wheel, such chain spanning the soil surface to be compacted.

In known apparatus of the kind heretofore described which employ a positive feed in place of the conventional friction drive between the compacting cylinder or plate and the soil surface (see also West German Gebrauchsmuster printed Specifications Nos. l,925,l90 and l,982,976) the chain is guided tangentially on the chain sprocket wheel or completely surrounds same. While in the one case the power transmission proved to be inadequate, difiiculties arose in the other case due to the severe chain reversal which led to increased frictional work and greater wear and by virtue of the fact that the sprocket wheel had to be adapted for disengagement to enable the chain to be drawn through the apparatus when the prime mover was at rest.

The invention avoids these difficulties by greatly reducing the chain reversal while ensuring adequate power .flow coupling between chain and sprocket wheel and by providing for easy detachability of the positive engagement between chain and chain sprocket. According to the invention, said apparatus comprises a .chain guiding system which is settable in a first position in which the .chain will be maintained in engagement with the sprocket wheel in the zone of a circumferential sector, and which is movable from said first position towards a second position in which the chain can be detached from engagement with the sprocket wheel.

In a preferred embodiment, the chain guiding system is pivotable about an axis disposed perpendicularly to the sprocket wheel axis so that the entire chain guiding system can be swung away after releasing a locking bolt or the like when it is desired for the chain to be pulled through free of the transmission.

In a preferred embodiment, the chain guiding system comprises two freely rotatable rollers which determine the extent of the sector of contact between the sprocket wheel .andthe chain, and further comprises a retaining plate, disposed between the rollers, and having a curvature corresponding to the curvature of the chain sprocket to prevent the chain from jumping out of the chain sprocket but without normally touching the chain.

With a chain arrangement of the kind heretofore described within the apparatus and in a further development of the invention it is possible to incorporate apparatus for the automatic changeover of the soil compactor. According to such an embodiment, the chain will traverse through tubular sections disposed upstream and downstream of the chain guiding system and being movably supported along their longitudinal axes and being able, under the bias of :stop abutments detachably mounted on the chain, to actuate a switch which will reverse the direction of motion of the apparatus. In particular, the system is so designed that the tubular sections act upon a switch lever which is urged by a compression return spring into one of two switch positions beyond the dead center disposed on both sides of the middle idling position .and being defined by stop abutments, each tubular section being appropriately constructed to initially compress a spring by a certain amount when said tubular section is displaced and only thereafter bearing upon the switch lever. The same tubular sections may also be provided with sensing fingers so that the direction of motion of the apparatus is reversed not only when the tubular sections strike the chain abutments but also if the sensing fingers come into contact with unforeseen obstacles in the feed path of the apparatus.

Since the soil compacting apparatus according to the invention is intended in particular to operate in ditches for pipelines or the like which are hardly wider than the apparatus itself, the engine starting shaft is disposed perpendicularly to the horizontally disposed sprocket wheel shaft.

I One embodiment of the invention is illustrated, by way of example only, in the accompanying drawings in which:

FIG. 1 is a partially sectioned part view of the soil compacting apparatus approximately along line 1-1 of FIG. 2, devices which are not relevant to the invention having been omitted;

FIG. 2 is a sectional view along the line Il-ll of FIG. 1

FIG. 3 is a sectional view along the line III-Ill of FIG. I; and

FIG. 4 is a view of a typical compactor embodying the invention.

The compacting rollers and the prime mover (not shown) and the transmission 2 of the soil compacting apparatus are mounted in a frame 1. The arrangement of these units is known and is not the subject of the invention. However, FIG. 4 shows a compactor of a type in the aforesaid German Specification No. 1,925,190 and showing a portion of the invention merely to illustrate the general type of machine with which the invention is concerned. A chain 3 passes through the apparatus centrally in the direction of its feed motion, said chain passing through tubular sections 4 which are supported in bearings 5 on the cross members of the frame 1 so that they may be displaced in the direction of the arrows 6 when, at the end of its feed, the apparatus moves in one direction against stop abutments 7 which are mounted on the chain 3.

That end of the tubular section 4 which projects beyond the frame 1, bears against the appropriate stop abutment 7 and is displaced inwardly due to the continuous feed motion of the apparatus (that is to say motion relative to the chain 3). The tubular sections 4 are mounted by means of offset tappets 8 on slides 9 which are guided on a rod 10 of the switching means for the transmission 2. If one slide 9 is displaced on the rod 10 owing to displacement of one of the tubular sections 4, said slide will initially compress a spring 11 which concentrically surrounds the rod 10 until a sleeve 12 strikes the shoulder 13 of a further sleeve 14 which acts on the arm 15 of a rocker lever 16 adapted to pivot around the pivoting pin 17.

' Unless the other arm 18 of the rocker lever 16 is locked in its neutral position by means of a handoperated bolt 19 as shown in FIG. 1 it will bear against one of the two stop abutments 20. It is thrust against said stop abutments by means of a compression return spring 21 which is inserted between the end of the arm 18 and a stationary abutment 22. The -position of the transmission indexing system is also the dead center position for the compression return spring 21 so that the arm 18 will be in one of two positions beyond the dead center when bearing on one of the abutments 20.

aforementioned rocker lever passes slightly beyond said 0-position, the stressed spring 13 and the return compression spring 21 thrust the rocker lever 16 into its other indexing position against the other stop abutment 20 thus causing the soil compacting apparatus to reverse the direction of its feed motion.

The same effect occurs if the sensing fingers 23, mounted by means of rod or tubular sections 24 on the tappets 8, strike an obstruction which extends into the path of movement of the apparatus. The direction of motion may also be reversed by means of a handlever 25.

Between the inner ends of the tubular sections 4 the chain 3 passes over the chain sprocket 26 of which only one half is visible in FIG. 1, while a chain guiding system, referenced in its entirety by the numeral 27, conceals the other half. The bearing system, construction and disposition of the chain sprocket 26 and the chain guide 27 is disclosed by FIGS. 2 and 3.

The chain sprocket 26, supported in a bearing pedestal 28 and in a further bearing pedestal which is not shown, is driven through a flexible coupling 29 by the prime mover, not shown, (usually an internal combustion engine). The bearing pedestal 28 is supported on the frame 1, as shown in FIG. 3. As disclosed in particular by FIG. 2, the chain 3 is guided over the upper part of the chain sprocket 26 and engages therewith only over a part of its circumference.

The magnitude of the angle of contact is determined by rollers 30 which are journalled to rotate freely between the cross members 31 of the chain guiding system 27. A curved guard plate 32, adapted to the curvature of the chain sprocket 26, is disposed between said cross members. The function of the guard plate is merely to prevent jumping out of the chain from the chain sprocket 26 and, by contrast to the rollers 30, is not normally in physical contact with the chain 3.

The cross members 31 which support the rollers 30 and the guard plate 32 between them are mounted on a support 33 adapted to pivot, through lugs 41, around a bolt 34 which is maintained in a stationary position by the bearing pedestal 28. In the working position of the chain guide 27 illustrated in FIGS. 2 and 3, said chain guide is prevented against pivoting by a bolt 35 which engages into a part 36, also mounted on the bearing pedestal 28. However, if the bolt 35 is withdrawn by its handle 37, the chain guide may be pivoted in the direction of the arrow 38 to release the chain 3 which may then be lifted out of the sprocket and may be pulled through freely through the apparatus without th eed for c u lin e chain 5 rocket 2 l'lie transmission a iiicorpora es an angle drive (not shown) which couples the engine starting shaft 39 (FIG. 1), extending upwardly, to the transmission shaft (and the engine flywheel) which extends in shaft 42 for driving shaft of the chain sprocket 26. The drive through the transmission 2 to shaft 42 is conventional.

We claim:

1. Soil compacting apparatus which is adapted to operate with rotatable unbalance and which will be positively driven along a chain by means of a driven sprocket wheel, characterized in that said apparatus comprises a chain guiding system which is settable in a first position in which the chain will be maintained in engagement with the sprocket wheel in the zone of a circumferential sector, and which is movable from said first position towards a second position in which the chain can be detached from engagement with the sprocket wheel, said chain guiding system being pivotable about an axis disposed perpendicularly to the sprocket wheel axis.

2. Soil compacting apparatus according to claim 1, characterized in that the chain guiding system is provided with two freely rotatable rollers which will determine the extent of the contact sector of the chain sprocket engaged by the chain.

3. Soil compacting apparatus according to claim 2 in which the chain guiding system is provided with a retaining plate having a curvature corresponding to the curvature of the chain sprocket and disposed between the rollers.

4. Soil compacting apparatus according to claim 1 including a switch for reversing the direction of the apparatus, tubular sections for actuating said switch, said tubular sections receiving said chain, said tubular sections being at positions upstream and downstream of said chain guiding system, means movably supporting said tubular sections in their longitudinal directions, and stop-abutments detachably mounted on the chain for engaging said tubular sections.

5. Soil compacting apparatus according to claim 4 including a switch lever that operates said switch, said tubular sections acting upon said switch lever, said switch lever having two positions on opposite sides of a deadcenter middle idling position, and a spring for moving said switch lever from one of said two positions past said idling position and to the other of said two positions upon movement of said lever to said idling posi tion.

6. Soil compacting apparatus according to claim 5 including an additional spring that is compressed by a tubular section a-defined amount following which said additional spring will apply a force to actuate said switch lever.

7. Soil compacting apparatus according to claim 4 including sensing fingers on said tubular sections for striking obstructions in the path of the apparatus.

8. Soil compacting apparatus according to claim 1 in which said sprocket wheel axis is horizontal, means including an engine for driving said sprocket wheel, and said engine has a starting shaft that is vertical.

* III UNITED" STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent NO. 3,6932513 I Dated September 26,1972

Inventor( s) Eberhard Borsutzki and Gerhard Liebmann It is certified that error appears in the above-identified patent and that said Letters Patent are hereby oorrected as shown below:

Col. 4, line 7, before "shaft 42" insert --parallel to the- Col. 4, line 54, change "sectio" to --section-- Signed and sealed this 1st day of May 1973.

(SEAL) Attest:

EDWARD M. FLETCHER, J'R. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 0 USCOMM-DC 60376-P69 U.$. GUVERNMENT PRINTING OFFICE! 1959 O366-33A 

1. Soil compacting apparatus which is adapted to operate with rotatable unbalance and which will be positively driven along a chain by means of a driven sprocket wheel, characterized in that said apparatus comprises a chain guiding system which is settable in a first position in which the chain will be maintained in engagement with the sprocket wheel in the zone of a circumferential sector, and which is movable from said first position towards a second position in which the chain can be detached from engagement with the sprocket wheel, said chain guiding system being pivotable about an axis disposed perpendicularly to the sprocket wheel axis.
 2. Soil compacting apparatus according to claim 1, characterized in that the chain guiding system is provided with two freely rotatable rollers which will determine the extent of the contact sector of the chain sprocket engaged by the chain.
 3. Soil compacting apparatus according to claim 2 in which the chain guiding system is provided with a retaining plate having a curvature corresponding to the curvature of the chain sprocket and disposed between the rollers.
 4. Soil compacting apparatus according to claim 1 including a switch for reversing the direction of the apparatus, tubular sections for actuating said switch, said tubular sections receiving said chain, said tubular sections being at positions upstream and downstream of said chain guiding system, means movably supporting said tubular sections in their longitudinal directions, and stop-abutments detachably mounted on the chain for engaging said tubular sections.
 5. Soil compacting apparatus according to claim 4 including a switch lever that operates said switch, said tubular sections acting upon said switch lever, said switch lever having two positions on opposite sides of a dead-center middle idling position, and a spring for moving said switch lever from one of said two positions past said idling position and to the other of said two positions upon movement of said lever to said idling position.
 6. Soil compacting apparatus according to claim 5 including an additional spring that is compressed by a tubular section a defined amount following which said additional spring will apply a force to actuate said switch lever.
 7. Soil compacting apparatus according to claim 4 including sensing fingers on said tubular sections for striking obstructions in the path of the apparatus.
 8. Soil compacting apparatus according to claim 1 in which said sprocket wheel axis is horizontal, means including an engine for driving said sprocket wheel, and said engine has a starting shaft that is vertical. 